In the ZZ/ZW sex determination system, which is the male genetic configuration?

In the ZZ/ZW sex determination system, the male genetic configuration is designated as ZZ. This system is distinct from the more commonly known XX/XY system found in many mammals. In ZZ/ZW, males possess two identical sex chromosomes (ZZ), while females have one Z and one W chromosome (ZW).

The rationale behind this configuration is that in species utilizing the ZZ/ZW system, the presence of two Z chromosomes typically results in male development, as these chromosomes are associated with the male phenotype. Conversely, the combination of one Z and one W chromosome leads to female development. Understanding this system helps clarify how sex is determined in certain organisms, particularly among birds, some reptiles, and some fish, providing insight into the diversity of genetic mechanisms behind sex determination across different species.